Clamping stand

ABSTRACT

A clamping stand, particularly for forming assembly stands or temporary platforms or the like, characterised by two levers connected in a pincer or scissor-like manner, the lower arm being in the form of a base and the other upper arm supporting a clamping jaw pivotable about a joint parallel to the joint, the two clamping jaws being clampable by a bending prop which connects the two bases and can be locked in an extended position.

United States Patent 1191 Sch'aftel 1451 Aug. 20, 1974 [54] CLAMPING STAND 2,589,520 3/1952 Wallenius 248/226 c 2,706,661 4/1955 C1 t 182/186 [76] Inventor: Walter Schafiel, Burgstallerstr. 7, 3,139,951 7/l964 332 82/186 8150 Hollklfchen, Germany 3,741,339 6/1973 Eubank [82/186 [22] Filed: Apr. 13, 1973 Primary Exammer-Remaldo P. Machado PP N03 350,781 Attorney, Agent, or Firm-Finnegan, Henderson,

Farabow & Garrett [30] Foreign Application Priority Data Apr' 14, 1972 Germany 2218233 [57] ABSTRACT A clamping stand, particularly for forming assembly [52] us. Cl......'. 182/226, 182/186 stands or temporary platforms or the like, character- [51] Int. Cl. Fl6m 11/00 ised y two levers nn t d in a pin er r s issor-like [58] Field of Search 182/186, 226, 182, 183, manner, the lower r i g in th form of a base and 182/184, 135, 176; 248/226 C 226 B the other upper arm supporting a clamping jaw pivotable about a joint parallel to the joint, the two clamp- [56] References Cit d ing jaws being clampable by a bending prop which UNITED STATES PATENTS connects the two bases and can be locked in an ex- 861,583 7 1907 Foster 182/176 tended posmon' 1,261,007 4/1918 Beardsley 182/186 9 Claims, 7 Drawing Figures PAIENIEB AUBZOISH snmzor 4.

Pmmznwszw v 3.830.340-

sum am 4 1 CLAMPING STAND The invention relates to a clamping stand, particularly for forming assembly stands, temporary platforms or the like.

There are known clamping stands comprising a claw which consists of two flexibly connected metal shoes and into each of which squared timber can be inserted from below, in which case a horizontally lying piece of squared timber can be clamped on the upper side of the claw when the squared timber is spread out or expanded into a V-shape. These clamping stands can only be used in connection with squared timber and are therefore very limited in their range of applications.

There are other known clamping stands consisting of two pipes or tubes standing relative to one another in a V-shape and provided with an upper clamping support, in which case a U-rail guide for connecting two clamping stands can be tightly clamped with the aid of the clamping support. These clamping stands also are limited in their application. v

The object of the invention is to provide a clamping stand which can be used in a more versatile manner with regard to the parts to be clamped at the top.

This problem is solved by two levers connected in a pincer-like manner, the lower arm of which lever is in fected by telescopically adjustable tubes which are guided so as to be vertically adjustable inside or outside the actual feet which are in the form of tubes. The height or vertical adjustability can in turn be effected by various bores, at a given distance from one another, and by means of a quick-acting plug acting as a retaining means.

the form of a base and the other upper arm of which bases and can be locked in a stretching position. Owing to the great reduction ratio between the pressure points of the clamping jaws and the bending prop, a considerable gripping force is produced ,betweenthe clamping jaws when the prop is extended. Furthermore, owing to the movability of the clamping jaws, square, rectangular, round and other shaped sections can be clamped and in any case are firmly supported.

It is particularly advantageous if the effective length of the bending prop is variable 50' that the opening width of the clamping jaws can be produced to correspond to the greatest variety of sections to be clamped. The length may be particularly simply varied of the bending prop is formed by an apertured rail or bar connected to one foot and by a U-rail which is connected to the other foot and overlaps the apertured bar, both the U-rail and the apertured bar being connectable by a round pin extending through both parts and forming the articulated joint.

Instead of varying the length of the bending prop or even in addition thereto, the lever joint can be adjusted by varying the spacing of the clamping jaws.

To simplify manufacture the lever arms and the clamping jaws are advantageously identical in design as far as possible. This may be achieved eg for the upper arms of the clamping stand because the latter are U- shaped parts directed towards one another with upright legs, to which the clamping jaws are connected and which are flexibly connected to their legs forming the lever joint, the legs of the U-shaped parts lying opposite one another comprising overlapping lower tongues by which they are flexibly connected to one another to form the lever joint, each tongue being bent in the overlapping area with the associated tongue of the opposite U-shaped part.

To further broaden the range of application, height or vertical adjustment of the clamping stand may be ef- The invention will be described below in more detail with the aid of schematic drawings of two practical embodiments.

FIG. 1 shows a side view of a clamping stand according to the invention;

FIG. 2 is a section along the line l1 shown in FIG.

FIG. 3 is a side view of a second embodiment of a clamping stand according to the invention;

FIG. 4 is a partial plan view of the clamping stand shown in FIG. 3, when viewed in the direction of the arrows II II;

FIG. 5 is a partial representation corresponding to FIG. 1 clearly illustrating a further embodiment of the bending prop;

FIG. 6 is a plan view of the embodiment shown in FIG. 5;

FIG. 7 shows a section VIVI shown in FIG. 6.

The clamping stand shown in FIG. 1 consists of two levers connected in a pincer or scissor-like manner by the joint pin 1 and each comprising an upper arm 2 and a lower arm 3. The lower arms 3, which serve as a base for the clamping stand, are pipes in which are guided vertically adjustable telescopic tubes 4 which comprise a plurality of longitudinally spaced bores 5 and can be 'locked in a great variety of slide-in positions with the aid of a quick-acting plug 6 acting as a retaining'member. The bases or stand pipes 3 are connected at the bottom by a bending prop or stay 7. The latter consists of an apertured bar or rail 9 connected to one lower arm 3 at 8 and a U-rail 11 which is connected to the other lower arm at 10 and overlaps the apertured bar from above with its web 12 which is reduced to a small section. The articulated joint of this bending support 7 forms a quick-acting plug 13 which can be brought into engagement with various holes 14 in the apertured bar 9 in order to vary the effective extended length of the bending prop 7 and therefore the opening width or the mutual spacing between the upper arms 2 of the clamping stand. By removing the quick-acting plug 13, the tow parts 9 and 11 of the bending prop can be separated from one another and pivoted upwardly so that the clamping stand may. be folded up and collapsed.

The upper arms 2 are U-shaped parts directed towards one another and welded to the top end of the lower arms 3 as well as being provided with upright sides 15 comprising overlapping lower tongues 16 by which the sides are connected to form the pincer or scissor-like joint 1. As can be best seen in FIG. 2, a tongue 16 of each upper arm is bent in the area overlapping with the associated tongue of the other upper arm, by the material thickness of this tongue, so that each U-shaped part is asymetrical with reference to the longitudinal median plane of the U-shape, but the two U-shaped parts are identical. A clamping jaw 17, U- shaped in cross-section, is pivotably connected to each upper arm 2 between the sides 15 with the aid of a pivot pin 18, about an axis parallel to the axis of the joint pin 1, and with the aid of the approximately triangularshaped U-shaped leg shown in FIG. 1, the U-shaped web acting as a clamping face 19. This clamping face is advantageously bent open at the top and bottom, as can be seen in FIG. 1.

Corresponding bending can also be provided in the vicinity of the side connections, as can be seen in FIG. 2, so that an object to be clamped between the clamping faces 19 only comes into contact with the edges of the clamping face 19.

Square, rectangular, round and other shaped sections can be clamped owing to the movability of the clamping jaws and in any case are firmly supported. The bending prop 7 which is adjustable in length permits the opening width of the clamping jaw 17 to be varied whereas the telescopic tubes 4 make height adjustment possible so that the clamping stand according to the invention is provided with great adaptability and versatility. Such a clamping stand usually serves as a support for working platforms in connection with at least one other stand e.g. for supporting beams. However, this type of clamping stand may also be designed as an independently fixed unit, with each arm 3 being formed by e.g. two spaced apart feet or with one arm acting as a single foot and the other arm acting as a double foot so that a three-legged arrangement is obtained. In either case a considerable clamping force can be produced owing to the great transmission ratio between the lower bending prop and the pressure points of the upper clamping jaws when the prop is forced down into an extended position. A more robust embodiment is shown in FIGS. 3 and 4. This clamping stand 20, together with the two levers flexibly connected at 2], is provided with stand pipes which form the upper arm 22 serving as a clamping jaw holder and the lower arm 23 serving as a base. As in the first embodiment, the two lower arms 23 in turn receive telescopic tubes 24 which, with the aid of a plurality of holes 25, make height adjustment possible and can be locked in the respective vertical position by means of a quick-acting plug 26. Corresponding to the first embodiment, the lower arms 23 are connected at the bottom by a bending prop 27 which consists of one flat bar or rail 29 connected to one lower arm at 28 as well as a U-rail 31 overlapping this flat bar and being connected to the other lower arm at 30. The bar 29 and the U-rai] 31 are flexibly connected in the centre at 33, the web 32 of a U-rail 31 acting as a stop to prevent excessive downward extending of the prop, whereas the upward buckling of the prop in the direction of the indicated arrow as well as in FIG. 1 is possible for opening the clamping jaws, an object to be supported being rigidly clamped by the stretching of the bending prop in accordance with the toggle lever principle after the article is introduced between the clamping jaws.

In contrast to the first embodiment shown in FIGS. 1 and 2, the length of the bending prop is not variable in the present case. Instead the joint 21 is formed by two oppositely lying U-shaped bands 35, each gripping around an upper arm 22 and being rigidly connected thereto, the sides of the two U-shaped bands overlapping one another and comprising, in the overlapping area, a row of holes 36 for receiving a quick-acting plug 37 which acts as a joint pin. The overlapping sides of the U-shaped bands are mutually bent, corresponding to the tongues 16 in FIG. 1, so that the two U-shaped bands may be identical in design. The opening width of the clamping jaws may be adjusted by removing the plug 37.

The associated clamping jaws are formed by U- shaped belts 38 each enclosing the upper arm 22 and being flexibly connected thereto at 39. Welded to the two ends of each U-shaped belt 38 is a clamping plate 40 between which an object to be clamped is received. In the present case the clamping jaws 38 can be advantageously replaced in accordance with the invention so that re-arrangement is possible for special work such as the thread cutting of pipes of special parts for receiving scaffolding to be erected or for the installation of slide rails for machine mounting. The rivet for flexibly connecting the U-shaped belt shown in FIG. 4 is then replaced by a quick-acting plug, as is also used with telescopic tubes.

In both embodiments the edges of the clamping faces are substantially drawn in only in a case where wodden pieces are to be securely gripped between the clamping jaws. The clamping faces may be differently shaped for other purposes.

The embodiments shown in FIGS. 5 to 7 concern a modification of the embodiment shown in FIG. 1, with the length of the bending prop being variable. The bending prop, generally designated by reference numeral 40, consists in turn of two levers 41 and 42 connected to the feet 3 at 8 and 10 and both having a U- shaped cross-section, one of which, i.e. the lever 41, overlaps the other lever 42. The lever 41 is provided on both sides 43 with a longitudinal slot 44 with upwardly directed locking grooves 45 for a locking pin 46 attached to the lever 42, which locking pin is adjustable along the longitudinal slot 44 and can engage on each of the locking grooves 45 depending on the desired length of the prop.

A locking device generally designated by reference numeral 47 is provided for securing the bending prop in the selected position, i.e. for securing the prop in a position shown in FIG. 5. This locking device is attached to one side 43 of the lever 41 and comprises a locking pin 48 which can be locked, under the tension of a spring 49, in holes 50 in the sides 51 of the other lever 42, the distance between the holes 50 being equal to the distance between the locking grooves 45. The locking pin 48 is guided through a sleeve 52 attached to the lever 41 and projects with a section 53 of its shank out of this sleeve and is force-fitted in a knob or ball 54 with which the locking pin 48 may be removed from the holes 50 by being pulled in opposition to the tension of the spring 49. A securing pin 55 is attached to the locking pin 48 to limit the lifting movement of the latter, said securing pin being guided through an elongated slot 56 in the sleeve 52 and secured against rotation.

The end of the locking pin 48 co-operating with the holes 50 comprises a bevel edge 57 which can be clearly seen in FIG. 7. When the lever is bent out of a previous bending position and into the stretched position, the bevel edge 57 slides downwardly over the outer side of the lever 42, and the locking pin 48 when reaching the associated locking hole, automatically engages therein.

I claim:

1. A clamping stand for forming an assembly stand for temporarily fixedly holding different objects having varied cross sections comprising a pair of levers pivotally connected together by a lever joint in a pincer-like manner, each lever having a lower arm forming a base for the stand and an upper arm, a pair of clamping jaws,

one jaw being pivotally mounted to each upper arm by a second joint parallel to said lever joint, a bendable prop attached to one end to the lower arm of one of said levers and at the other end to the other of said levers, said prop being bendable intermediate said levers about a third joint, means for locking said prop in an extended position, said jaws beingmovable from (a) a spaced apart position when said lower arms are adjacent to each other to their (b) closest position when said lower arms are spaced apart and said prop is in said extended position, one of said lever joints and third joints comprising a removable pivot pin and a pin receiving member section extending from each of said levers in overlappingrelationship, at least one section having a plurality of spaced apart holes and the other section having at least one hole for receiving said pivot pin, the distance between said jaws when said jaws are in said closest position being adjustable and determined by insertion of said pivot pin into one of said holes in -each of said sections.

2. A clamping stand as defined in claim 1 wherein said lever joint is adjustable in length between said levers to effect adjustment of the distance between said jaws when said jaws are in their closest position.

3. A clamping stand as defined in claim 1 wherein each of said upper arms includes a back and upright sides forming a U-shaped member directed toward the corresponding member of the other arm, the sides of one member being rotatable joined to the sides of the other member to form said lever joint.

4. A clamping stand as defined in claim 3 wherein each clamping jaw has a U-shaped cross-section and is pivotally connected between said upright sides of said upper member.

5. A clamping stand as defined in claim 3 wherein each of said upper arms further include tongues extending from the lower end of said upright arms and overlapping a corresponding tongue extending from the other upper arm, at least one tongue on each of said upper arms being bent to permit overlap with its corresponding tongue, and a pivot means joining said overlapping tongues to permit rotatable movement between said upper arms.

6. A clamping stand as defined in claim 1 wherein said prop is formed of a first bar attached at one end to one lower arm, a U-rail attached at one end to the other lower arm and being pivotally joined at the other end thereof to the other end of said first bar by a pivot pin, said U-rail having a portion overlapping the top of said first bar spaced from said pivot pin.

7. A clamping stand for forming an assembly stand for temporarily fixedly holding an object comprising a pair of levers pivotally connected together by a lever joint in pincer-like manner, each lever having a lower arm forming a base for the stand and an upper arm, a pair of clamping jaws each being formed by a U-shaped member pivotaly mounted to one of said upper arms by a second joint parallel to said lever joint, said jaws also including a clamping plate at the inward end of said U- shaped member, said lever joint being formed by a first U-shaped band engaging one of said levers and a second U-shaped band engaging the other of said levers, said first and second bands overlapping each other and having a plurality of spaced holes in the overlapping area for receiving a removable pivot pin, a bendable prop attached at one end to the lower arm of one of said levers and at the other end to the other of said levers, said prop being bendable intermediate said levers about a third joint, means for locking said prop in an extended position, said jaws being movable from a spaced apart position wherein said lower arms are adjacent to each other to their closest position wherein said lower arms are spaced apart and said prop is in said extended position, said lever joint permitting selective variation of the distance between said jaws when said jaws are in said closest position.

8. A clamping stand as defined in claim 1 wherein said bendable prop comprises a first lever connected at one end to one lower arm, a second lever connected at one end to the other lower arm, the other end of said first lever overlapping the other end of said second lever, said first lever having a longitudinal slot and a plurality of locking grooves communicating with such slot, said second lever having a locking pin adapted to engage selectively said locking grooves.

9. A clamping stand as defined in claim 1 wherein said bendable prop comprises a first lever connected at one end to one lower arm, a second lever connected at one end to the other lower arm, the other end of said first lever overlapping the other end of said second lever, said first lever having a plurality of spaced first holes, said second lever having a plurality of spaced second holes, said first and second holes being spaced equally through the overlapping sections of said first and second lever, a locking device including a locking pin adapted to be received by selected one of said first and one of said second holes when said prop is in its extended position, said pin being supported in a housing and spring biased toward its hole engaging position. 

1. A clamping stand for forming an assembly stand for temporarily fixedly holding different objects having varied cross sections comprising a pair of levers pivotally connected together by a lever joint in a pincer-like manner, each lever having a lower arm forming a base for the stand and an upper arm, a pair of clamping jaws, one jaw being pivotally mounted to each upper arm by a second joint parallel to said lever joint, a bendable prop attached to one end to the lower arm of one of said levers and at the other end to the other of said levers, said prop being bendable intermediate said levers about a third joint, means for locking said prop in an extended position, said jaws being movable from (a) a spaced apart position when said lower arms are adjacent to each other to their (b) closest position when said lower arms are spaced apart and said prop is in said extended position, one of said lever joints and third joints comprising a removable pivot pin and a pin receiving member section extending from each of said levers in overlapping relationship, at least one section having a plurality of spaced apart holes and the other section having at least one hole for receiving said pivot pin, the distance between said jaws when said jaws are in said closest position being adjustable and determined by insertion of said pivot pin into one of said holes in each of said sections.
 2. A clamping stand as defined in claim 1 wherein said lever joint is adjustable in length between said levers to effect adjustment of the distance between said jaws when said jaws are in their closest position.
 3. A clamping stand as defined in claim 1 wherein each of said upper arms includes a back and Upright sides forming a U-shaped member directed toward the corresponding member of the other arm, the sides of one member being rotatable joined to the sides of the other member to form said lever joint.
 4. A clamping stand as defined in claim 3 wherein each clamping jaw has a U-shaped cross-section and is pivotally connected between said upright sides of said upper member.
 5. A clamping stand as defined in claim 3 wherein each of said upper arms further include tongues extending from the lower end of said upright arms and overlapping a corresponding tongue extending from the other upper arm, at least one tongue on each of said upper arms being bent to permit overlap with its corresponding tongue, and a pivot means joining said overlapping tongues to permit rotatable movement between said upper arms.
 6. A clamping stand as defined in claim 1 wherein said prop is formed of a first bar attached at one end to one lower arm, a U-rail attached at one end to the other lower arm and being pivotally joined at the other end thereof to the other end of said first bar by a pivot pin, said U-rail having a portion overlapping the top of said first bar spaced from said pivot pin.
 7. A clamping stand for forming an assembly stand for temporarily fixedly holding an object comprising a pair of levers pivotally connected together by a lever joint in pincer-like manner, each lever having a lower arm forming a base for the stand and an upper arm, a pair of clamping jaws each being formed by a U-shaped member pivotaly mounted to one of said upper arms by a second joint parallel to said lever joint, said jaws also including a clamping plate at the inward end of said U-shaped member, said lever joint being formed by a first U-shaped band engaging one of said levers and a second U-shaped band engaging the other of said levers, said first and second bands overlapping each other and having a plurality of spaced holes in the overlapping area for receiving a removable pivot pin, a bendable prop attached at one end to the lower arm of one of said levers and at the other end to the other of said levers, said prop being bendable intermediate said levers about a third joint, means for locking said prop in an extended position, said jaws being movable from a spaced apart position wherein said lower arms are adjacent to each other to their closest position wherein said lower arms are spaced apart and said prop is in said extended position, said lever joint permitting selective variation of the distance between said jaws when said jaws are in said closest position.
 8. A clamping stand as defined in claim 1 wherein said bendable prop comprises a first lever connected at one end to one lower arm, a second lever connected at one end to the other lower arm, the other end of said first lever overlapping the other end of said second lever, said first lever having a longitudinal slot and a plurality of locking grooves communicating with such slot, said second lever having a locking pin adapted to engage selectively said locking grooves.
 9. A clamping stand as defined in claim 1 wherein said bendable prop comprises a first lever connected at one end to one lower arm, a second lever connected at one end to the other lower arm, the other end of said first lever overlapping the other end of said second lever, said first lever having a plurality of spaced first holes, said second lever having a plurality of spaced second holes, said first and second holes being spaced equally through the overlapping sections of said first and second lever, a locking device including a locking pin adapted to be received by selected one of said first and one of said second holes when said prop is in its extended position, said pin being supported in a housing and spring biased toward its hole engaging position. 